Imaging element

ABSTRACT

Imaging elements are provided. An imaging element has a wireless communication circuit adapted to detect a wireless communication signal and to generate a control signal; an illumination circuit having an illumination element, the illumination circuit being adapted so that the illumination element generates light at an intensity that is based upon the control signal and a body containing the wireless communication circuit and the light source, wherein the body occupies a space that is less than about five cubic millimeters. The imaging element can also incorporate radiation sensors and can provide wireless signals indicative of sampled radiation.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is related to U.S. Serial No. (Attorney Docket No.89233RRS) entitled DISPLAY, in the name of Kerr et al.; and U.S. SerialNo. (Attorney Docket No. 89234RRS) entitled METHODS FOR MAKING DISPLAY,in the name of Kerr et al., all filed concurrently herewith.

Reference is made to commonly assigned, co-pending application U.S. Ser.No. 10/631,092, entitled A DIGITAL IMAGING ELEMENT in the name of DanielHaas, filed on Jul. 31, 2003 and incorporated herein by reference.

FIELD OF THE INVENTION

The invention relates generally to the field of light emitting imagedisplays.

BACKGROUND OF THE INVENTION

There is a general desire in the art of display technology to providedisplays with high-resolution as measured in a number of imagingelements per unit area of the display surface and to provide displaysthat are low in cost. These objectives can be difficult to achieve in asingle display. In particular, it is conventionally known to form adisplay device by depositing a plurality of individual light emittingmaterials in a pattern on a surface. These deposits of light emittingmaterial are adapted to radiate light when exposed to electrical energyand are referred to herein as light emitting elements. Controlelectronics are also deposited on the surface of such a display thatenable a controller to selectively provide a controlled amount power toeach image display element. Such control circuits are generally known inthe art as a “backplane”.

It will be appreciated that both the light emitting elements andbackplane require a certain amount of the space on the surface. As thenumber of light emitting elements increases, there is a concomitant needfor an ever-larger number of control lines in the backplane. However, asthe number of light emitting elements per unit area on a displayincreases, there is a decrease in available space between light emittingelements for the control lines and other circuits of the backplane.Therefore, as the number of light emitting elements in the displayincreases, it becomes substantially more difficult to define a backplaneon the same surface as the light emitting elements.

One way to solve this problem is to the form a display using a pluralityof layers. In a first layer formed on the surface, light emittingelements are formed on the surface in a first layer and a second layeris overlaid onto the first layer with the second layer having backplanecircuits arranged to cooperate with the light emitting elements of theimaging plane. This approach can cause a variety of problems. Forexample, inter-layer registration problems become difficult to solve inhigh-resolution displays. This is because as the size of the lightemitting elements is reduced it becomes increasingly difficult to alignthe circuits of the backplane with appropriate light emitting elementsformed as another layer on the surface. Further, the forming of multiplelayers adds assembly steps and introduces the possibility of damagingthe light emitting elements in the process of applying the backplane. Itwill be appreciated that, even a single damaged light emitting elementin a display can introduce an artifact in a displayed image that rendersthe display unsatisfactory for use by a consumer.

There is also desire in the art to form displays using non-conventionalsurfaces such as flexible substrates. One barrier to the development ofdisplays on flexible substrates is that it is difficult to maintain theintegrity of the relationship between the backplane and the lightemitting elements when the surface upon which they are formed can bedeformed. Further, there is a desire to form displays using non-flatsurfaces such as curved or non-flat contours, fabrics, bottles, and thelike as substrates, however, it is difficult to form backplanes usingsuch surfaces.

Accordingly what is needed in the art an imaging element that can beused to make displays without requiring complex backplane structures.What is also needed in the art is an imaging element that can be used tomake displays on non-conventional surfaces and/or flexible surfaces.

SUMMARY OF THE INVENTION

In one aspect of the present invention, an imaging element is provided.The imaging element has a wireless communication circuit adapted todetect a wireless communication signal and to generate a control signal;an illumination circuit having an illumination element, the illuminationcircuit being adapted so that the illumination element generates lightat an intensity that is based upon the control signal and a bodycontaining the wireless communication circuit and the light source,wherein the body occupies a space that is less than about five cubicmillimeters.

In another aspect of the invention, an imaging element is provided. Inthis aspect, the imaging element has a radiation sensor adapted to senseradiation that is incident on the radiation sensor during an exposureperiod; a sensor driver adapted to determine an amount of radiation; anillumination circuit having an illumination element. The illuminationcircuit is adapted so that the illumination element generates light atan intensity that is based upon an control signal. A wirelesscommunication circuit is adapted to detect a wireless communicationsignal and to generate a control signal based upon the wirelesscommunication signal and is further adapted to generate a wirelesscommunication signal indicative of the amount of sensed radiation duringan exposure period; and a body containing the wireless communicationcircuit and the light source. Wherein the body occupies a space that isless than about five cubic millimeters.

In still another aspect of the invention an imaging element is provided.In this aspect, a radiation sensor is provided and is adapted to senseradiation that is incident on the radiation sensor including the amountof light emitted by the illumination element. A sensor driver is adaptedto determine an amount of radiation radiate by the illumination elementbased upon the sensed radiation during an exposure period. Anillumination circuit is also provided having an illumination element,the illumination circuit is adapted so that the illumination elementgenerates light at an intensity that is based upon an control signal; acalibration circuit adapted to monitor the amount of light sensed by theradiation sensor and to adjust the amount of light emitted by theillumination element in response to control signals so that the amountof light corresponds to an amount of light that is to be generated bythe illumination circuit in response to the control signal. A bodycontains the wireless communication circuit and the light source whereinsaid body occupies a space that is less than about 5 cubic millimeters.

In a further aspect of the invention an imaging element is provided. Inthis aspect of the invention, a radiation sensing and emitting materialoperable to provide a signal indicative of radiation that is incident onthe radiation sensor and to generate radiation when energy is introducedinto the radiation sensing and emitting material. A sensor driver isadapted to determine an amount of radiation sensed by the radiationsensing and emitting material. An illumination circuit is provided, theillumination circuit being adapted to controllably introduce energy intothe radiation sensing and emitting material so that the radiationsensing material emits radiation at an intensity that is based upon acontrol signal. A wireless communication circuit is adapted to detect awireless communication signal and to generate a control signal basedupon the wireless communication signal and further adapted to generate awireless communication signal indicative of the amount of sensedradiation during an exposure period; and a body containing the wirelesscommunication circuit and the light source, wherein the body occupies aspace that is less than about five cubic millimeters.

BRIEF DESCRIPTION OF THE DRAWINGS

While the specification concludes with claims particularly pointing outand distinctly claiming the subject matter of the present invention, itis believed that the invention will be better understood from thefollowing description when taken in conjunction with the accompanyingdrawings, wherein:

FIG. 1A shows top cutaway view of a one embodiment of an imaging elementof the present invention;

FIG. 1B shows top cutaway view of another embodiment of an imagingelement of the present invention;

FIG. 1C shows top cutaway view of another embodiment of an imagingelement of the present invention;

FIG. 2 shows a top partial section view of another embodiment of animaging element of the present invention;

FIG. 3 shows exterior view of one embodiment of the embodiment of FIG.2;

FIG. 4 shows a partial cross-section view of the embodiment of FIG. 2;

FIG. 5A illustrates a sectional view of a first embodiment of a displayusing imaging elements;

FIG. 5B illustrates a sectional view of a second embodiment of a displayusing image elements;

FIG. 6 shows the display section of FIG. 5A having a top surface adaptedwith the microlenses;

FIG. 7 shows an embodiment of an imaging element having a memory;

FIG. 8 illustrates one embodiment of an imaging element having aradiation sensor;

FIG. 9 shows a block diagram schematic of one example of an imagingelement having a light sensor and a sensor driver circuit andtransmitter;

FIG. 10 is a block diagram schematic of an imaging element adapted foruse in sensing x-ray radiation;

FIG. 11 illustrates an embodiment of an imaging element having wirelesscommunication system that receives light signals;

FIG. 12 illustrates an embodiment of an imaging element having wirelesscommunication system that receives and transmits light signals;

FIG. 13 illustrates a block diagram view of an imaging system using asensing display;

FIG. 14 illustrates a display having a scintillator plate havinggrouping transceivers;

FIG. 15 illustrates a display having grouping transceivers andintermediate grouping transceivers;

FIG. 16 shows a partial side view of the formation of a sensing displayformed using fluidic self-assembly techniques;

FIG. 17 illustrates the use of an electromagnetic field to help orientimaging elements to engage cavities in a display formed using fluidicself-assembly techniques;

FIG. 18 is a side illustration an embodiment of a display formed bycoating techniques;

FIG. 19 is a top plane view of the display of FIG. 18;

FIG. 20 shows an embodiment of a display having a overcoat layer;

FIG. 21 shows an embodiment of the sensing display having imagingelements on two sides of a substrate;

FIG. 22 illustrates one embodiment of a method for determining locationsof imaging elements on a display;

FIG. 23 illustrates another embodiment of a method for determininglocations of imaging elements on a display;

FIG. 24 illustrates another embodiment of an imaging element; and

FIG. 25 shows another embodiment of an element having a multiple partillumination element.

To facilitate understanding, identical reference numerals have beenused, where possible, to designate identical elements that are common tothe figures.

DETAILED DESCRIPTION OF THE INVENTION

The present description is directed in particular to elements formingpart of, or cooperating more directly with, apparatus in accordance withthe invention. It is to be understood that elements not specificallyshown or described may take various forms well known to those skilled inthe art.

FIGS. 1A-1C show top cutaway views of one embodiment of an imagingelement 20 of the present invention. In the embodiment of FIG. 1A,imaging element 20 comprises a wireless communication circuit 22, anillumination circuit 24 and a support 26. Wireless communication circuit22 comprises, in this embodiment, a radio frequency receiver circuit 30and an antenna 32. Antenna 32 is adapted to receive radio frequencysignals and to provide the received signals to radio frequency receivercircuit 30. Radio frequency receiver circuit 30 is adapted to processthe radio frequency signals received by antenna 32 and, in certainembodiments, to extract energy for operation from the radio frequencysignal received by antenna 32.

Radio frequency receiver circuit 30 has an identification codeassociated therewith and is adapted to sense whether a received signalhas the associated identification code. When radio frequency receivercircuit 30 detects a radio frequency signal having the associatedidentification code, radio frequency receiver circuit 30 is adapted togenerate an illumination control signal having a value that is basedupon an illumination value that is encoded in the received wirelesscommunication signal. Radio frequency receiver circuit 30 provides theillumination control signal to illumination circuit 24. In certainembodiments, radio frequency receiver circuit 30 can also be adapted toreceive certain radio frequency signals that contain generic instructioncodes to which radio frequency receiver circuit 30 will react despitethe absence of an identification code specific to imaging element 20.For example, in such embodiments, radio frequency receiver circuit 30can be adapted to receive codes such as “all off” or “reduce brightness”that generically apply to an entire set of imaging elements 20 when suchimaging elements 20 are used collectively in a display as will bedescribed in greater detail below.

Illumination circuit 24 has an illumination control circuit 36 and anillumination element 38. Illumination control circuit 36 is anelectrical circuit that is adapted to control an amount of electricalenergy passing from a power source to the illumination element 38 basedupon the control signal received from radio frequency receiver circuit30. Illumination element 38 can comprise any material that is adapted toreceive electrical energy and to generate an amount of light inproportion to the amount of received electrical energy. In this regard,illumination element 38 can comprise, for example, a light emittingdiode, an organic light emitting diode element, a florescent orincandescent light element, or an electroluminescent element.Illumination element 38 can be adapted to provide one wavelength,frequency, or color of light or multiple wavelengths, frequencies orcolors of light.

Illumination element 38 can take on any of a variety of shapes,including, for example, the rectangular shape illustrated in FIG. 1A aswell as circular, square or other convenient shapes.

In one embodiment, radio frequency receiver circuit 30 is adapted toprovide an illumination control signal in the form of a voltage signalhaving an amplitude that varies in accordance with the illuminationvalue in a received radio frequency signal. In this embodiment,illumination control circuit 36 comprises a voltage controlled gate suchas a transistor that is electrically in series between the power sourceand the illumination element 38. Illumination control circuit 36 isadapted to receive a control signal having a voltage within a range andto control the amount of energy passing to the illumination element 38based upon the control signal.

In another example embodiment, radio frequency receiver circuit 30 isadapted to receive a radio frequency signal that contains anillumination value and a light characteristic value that defines acharacteristic of the light to be emitted by illumination circuit 24.The light characteristic value can define, for example, a preferredwavelength, frequency or color for the light. In response to this, radiofrequency receiver circuit 30 generates an illumination control signalthat is based upon both of illumination control value and the lightcharacteristic value. In such an embodiment, illumination circuit 24 hasan illumination control circuit 36 and an illumination element 38 thatare capable of selectively generating light in more than one wavelength,frequency, or color. For example, illumination control circuit 36 can beadapted to drive illumination element 38 in a variety of differentmanners to achieve different colors. In another example, illuminationelement 38 can be provided with a combination of separate areas that areeach adapted to radiate light having a particular wavelength, frequencyor color and that can be selectively actuated by illumination controlcircuit 36 to provide light having characteristics called for in theillumination control value and/or light characteristic value in theradio frequency signal.

It will also be appreciated, from this embodiment, that the combinationof wireless communication circuit 22 and illumination circuit 24 providean imaging element 20 that generates an amount of light that is basedupon the illumination value contained in a wireless signal received byradio frequency receiver circuit 30 and addressed to radio frequencyreceiver circuit. By using the codes, a transmitter (not shown) cantransmit signals that individually address single imaging elements 20 inan array comprising a plurality of imaging elements 20 for purposesincluding but not limited to controlling the amount of light emitted byeach imaging element 20 without need for backplane control wires.

In FIGS. 1A-1C, embodiments of imaging element 20 are shown thatcomprise a body 40 for the wireless communication circuit 22 and theillumination circuit 24. Body 40 provides protection for wirelesscommunication circuit 22 and illumination circuit 24 and defines anouter surface 42 for light emitting element 20. In the embodiment shownin FIGS. 1A and 1B, body 40 is shown in a circular form. However, thisis not necessary. Body 40 can have a variety of shapes as desired by thefunctional and/or aesthetic requirements of the use to which imagingelement 20 is put. For example, such as the shape illustrated in FIG.1C. Typically, body 40 will completely enclose wireless communicationcircuit 22 and illumination circuit 24.

Generally speaking, body 40 can be made from a wide variety ofmaterials. For example, body 40 can comprise a thermoplastic, a glass,an organic material, or an inorganic material. Typically, body 40 isprovided on imaging element 20 so as to provide protection to preventmaterials in an environment within which the imaging element 20 isplaced from contacting wireless communication circuit 22 or illuminationcircuit 24 to thereby protect wireless communication circuit 22 andillumination circuit 24 or any other circuits or systems of imagingelement 20 from environmental degradation. For example, body 40 can beformed as a material that is applied to communication circuit 22 and/orillumination circuit 24 so as to provide a barrier to preventenvironmental contaminants from contacting communication circuit 22 orillumination circuit 24. Examples of such materials include moistureresistant barrier materials, thermally resistant barrier materials,shock resistant materials, particulate matter resistant materials,biocidal materials, radiation resistant materials and materials adaptedfor electrical field insulation. Alternatively, body 40 can be adaptedwith such materials such as by coating or otherwise applying barrierlayers of such materials on or in body 40. Further, body 40 can beadapted with combinations of such materials.

Body 40 can also be formed from or adapted with materials that areadapted to prevent unwanted migration of materials from within body 40into the environment. For example, body 40 can formed from materials orotherwise adapted to prevent migration of materials used in theformation of wireless communication circuit 22 or illumination circuit24 so as to extend the life of these components. Body 40 can completelyencapsulate communication circuit 22, illumination circuit 24 andsupport 26. Alternatively, body 40 can be formed at least in part usingsupport 26 so that support 26 comprises at least part of an outersurface 42 of body 40 and support 26 combined to form an outer surface42.

Imaging element 20 is generally small sized, occupying space that isless than about 5 cubic mm. However, the overall size and shape ofimaging element 20 can be defined in any number of ways. When imagingelement 20 is adapted for use in relatively high resolution displays,imaging element 20 can have a size that is substantially less than about5 cubic mm and can have, for example and without limitation, a size thatis, the order of less than 0.001 cubic mm.

Typically, body 40 can be made from transparent or translucent materialsso that light emitted by the illumination circuit 24 can be seen outsideof outer surface 42. In one embodiment, body 40 is formed from amaterial that is adapted to absorb selected wavelengths, frequency, orcolors of light. In another embodiment, body 40 is made of a transparentmaterial such as a glass or clear thermoplastic.

In the embodiment of FIG. 1B, body 40 is formed in part from a deposit alight emitting material 37 that emits light when exposed to energy, andsuch material is used to form an illumination element 38 within body 40.In this embodiment, illumination control circuit 36 is adapted withelectrodes 35 that apply electrical energy to the deposit of lightemitting material 37. As is shown in FIG. 1C, deposit of light emittingmaterial 37 is applied within a matrix of material forming body 40.

Imaging element 20 can derive power for operation from a variety ofsources. In the embodiments shown in FIG. 1A-1C, imaging element 20 hasa radio frequency receiver circuit 30 that is adapted to deriveoperational power from radio frequency signals that are broadcastproximate to the radio frequency receiver circuit 30. For example, radiofrequency signals that can be received by a radio frequency receivercircuit 30 and used to provide the power for operational purposesincluding, but not limited to, signals used to send illumination valuesto the imaging element 20 and signals intended for transmission to otherimaging elements 20 in an array of such elements. Alternatively, radiofrequency receiver circuit 30 and antenna 32 can be adapted to detect awireless signal that is adapted to provide power to imaging elements 20for operation and illumination without such signal necessarily havingillumination values encoded therein. Power obtained for operationalpurposes can be used for purposes including but not limited operatingwireless communication circuit 22, radio frequency receiver circuit 30,

Turning now to FIGS. 2-4 what is shown, respectively, is a top partialsection view, an exterior side view, and a partial cross-section ofanother embodiment of imaging element 20. In this embodiment, imagingelement 20 has a body 40 with a first electrically conductive portion 44on outer surface 42, a second electrically conductive portion 46 and anelectrical insulator 48 therebetween. Electrical conductors 52 and 54provide electrical pathways from first electrically conductive portion44 and from second electrically conductive portion 46 to wirelesscommunication circuit 22 and/or illumination circuit 24. This allows apower supply that is separate from imaging element 20 to provide powerfor use in operating any or all of radio frequency receiver circuit 30,illumination control circuit 36, or illumination element 38.

FIG. 5A shows one section of a display 60 that is adapted to use theimaging elements 20 of the embodiment of FIGS. 2-4. As is shown in FIG.5A, a first layer 62 of display 60 is provided and a first conductivelayer 64 is formed thereon. A plurality of imaging elements is providedin an array 71 on first conductive layer 64 with second electricallyconductive portion 46 thereon. A second conductive layer 66 is formedseparate from first conductive layer 64 and in contact with the firstelectrically conductive portion 44 thereon. The conductive layers 64 and66 can be formed of conventional conductive material such as a metaldeposits or metallic coatings, a semi-conductor coating and the like. Incertain embodiments, it may be useful to provide a conductive layer thatis essentially transparent. For such purposes a material such as IndiumTin Oxide, pentazine and the like. This listing of such essentiallytransparent conductive materials is illustrative only and is notlimiting.

In the embodiment shown, an electrically insulative layer 72 is disposedbetween first conductive layer 64 and second conductive layer 66. Theelectrically insulative layer 72 can comprise, generally, any dielectricmaterial including, but not limited to, air, inert gasses, and othergasses, that generally that are not conductive with a range of expectedoperating conditions. Other materials such as thermoplastic materials,organic materials having dielectric properties, and inorganic materialshaving dielectric properties can be used

As shown in FIG. 5A, a power supply 74 provides electrical energy toimaging elements 20 by way of electrically conductive layers 64 and 66.Power supply 74 can comprise, for example, a battery, fuel cell, linevoltage, rectified line voltage or any other conventional source ofelectrical energy. In the embodiment shown in FIG. 5, a power supply 74is provided in the form of a battery formed on a layer 76 on display 60.Layer 76 is electrically connected to second conductive layer 66directly, and is connected to first electrically conductive layer 64 (asnecessary) by an interlayer power connector 78 that is insulated fromcontact with second electrically conductive layer 66. Such a battery canbe of a rechargeable type. Power supply 74 can be formed as a part ofdisplay 60 in ways other than providing a battery layer, can be externalto display 60 with connectors adapted to join power supply 74 to firstconductive layer 64 and second conductive layer 66.

It will be appreciated from the above that because the amount of lightemitted by imaging elements 20 of display 60 is controlled by way ofwireless signals it is not necessary to separately control the amount ofelectrical energy actually delivered to each imaging element 20.Accordingly, power supply 74 can provide electrical energy in a commonfashion to all of imaging elements 20 in an array 71 by way of firstconductive layer 64 and second conductive layer 66 that do not haveindividual paths to each imaging element. This greatly simplifiesassembly and design of display 60 as, in some embodiments, firstconductive layer 64 and second conductive layer 66 can comprise layersof conductive material that do not have a predetermined pattern ofconductive material and therefore do not require registration withindividual imaging elements 20.

In other embodiments electrically conductive layers 64 and 66 can bepatterned as desired. However, as there is no need to individuallyregulate the amount of energy flowing to each element in a patternedconductive layer, larger conductors can be used and registrationproblems between the conductive layers and the imaging elements 20 aregreatly reduced. This reduces the challenge properly assembling display60 and provides a display 60 with increased durability.

In still other embodiments, a single conductive layer such as firstconductive layer 64 can be provide with a pattern of alternatingconductors adapted to engage first electrically conductive portion 44and second electrically conductive portion 46 to define a difference ofpotential to provide power thereto. Here too, because there is no needto define individually patterned conductors for each individual imagingelement 20, a display 60 of this type can be more easily manufacturedand can offer greater durability than existing displays.

In a further embodiment shown in FIG. 5B, imaging elements 20 aredisposed between a first layer 62 and a second layer 64 of a display 60that is adapted to provide a fluid around imaging elements 20, withfluid 65 that is adapted so that a difference of potential between afirst electrically conductive portion 44 and disposed in one portion offluid 65 and a second electrically conductive portion 46 of imagingelements 20 disposed in a different portion of a fluid 65. Fluid 65 canbe provided as a static fluid in a liquid form, gel form or in the formof a flow of fluid.

In certain embodiments, the orientation of imaging element 20 withrespect to support 26 can be of importance. Further, the orientation ofimaging element 20 relative to contacts adapted to engage first andsecond conductive portions 44 and 46 can be of importance. In theembodiment shown in FIG. 5A, each imaging element 20 is shown optionallyadapted with a magnetic polarity so that when it is exposed to amagnetic field, imaging element 20 will orient itself in accordance withsuch a field. Such magnetic orientation can be used to properly alignwith imaging elements 20 of array 71 to ensure that light radiated byeach imaging element 20 in array 71 is radiated in a desired manner orin a desired direction and/or to ensure that the first electricallyconductive portion 44 and second electrically conductive portion 46 areproperly aligned to engage contacts such as a conductive layer 64 or 66that provide electrical energy from power supply 74. In this regard,body 40 can be formed of or otherwise provided with a coating of amaterial that allows imaging element 20 to react to an applied electricfield. Other forms of electromagnetic bias can be introduced into anillumination element 38 for this purpose including but not limited to anelectrostatic bias.

A second layer 68 is shown in FIG. 5A. Second layer 68 can be used tosecure imaging elements 20, and conductive layer 64 and optionally, toalso secure conductive layer 66, insulative layer 72, power supply 74,battery layer 76 and interlayer power connector 78 as desired. Further,second layer 68 can be adapted to join with first layer 62 to provide anenclosure to encapsulate imaging element 20, and conductive layer 64 andoptionally, to also secure conductive layer 66, insulative layer 72,power supply 74, battery layer 76 and interlayer power connector 78 asdesired.

In the embodiment that is shown in FIG. 5A, second layer 68 isoptionally applied to form a top surface 69 of display that does nothave protrusions caused by imaging elements 20, and conductive layer 64and optionally, to also secure conductive layer 66, insulative layer 72,power supply 74, battery layer 76 and/or interlayer power connector 78.

There is a general desire in the art for the displays 60 that are therelatively thin. Using imaging elements 20 in the present invention, itis possible to form a display having the very little thickness. In thisregard, the size of imaging elements 20 makes it possible to form adisplay 60 having a first layer and a second layer that are separated bydistance of less than 1 mm. Thus, imaging elements 20 of the presentinvention can be used to form both displays having conventionalthicknesses, as well as displays having greatly reduced thicknesses.Further, it will be appreciated that a thickness of a display 60 thatcan be formed from imaging elements 20 is also reduced because a display60 formed using imaging elements 20 can have fewer layers of the typethat are used for a backplane purposes in conventional imagingtechnologies.

As shown in FIG. 6, top surface 69 can also be patterned or otherwiseadapted with for example, micro-lenses M to focus light traveling to orfrom, imaging elements. As is also illustrated in FIG. 6, in oneembodiment, an optional overcoat layer 70 can be provided on top surface69, imaging elements 20 and/or other portions of display 60

In one embodiment, first layer 62, second layer 68 and/or overcoat layer70 can comprise a transparent material or a nearly transparent material.In some embodiments, first layer 62, second layer 68 and/or overcoatlayer 70 can comprise any of a number of less than transparent materialssuch as diffusion materials, filtering material and the like.Additionally, first layer 62, second layer 68 and/or overcoat layer 70can also optionally be formed from materials that can prevent display 60from damage that can occur when it is exposed to thermal, electrical,magnetic or other forms of energy such as materials that block the flowof ultraviolet or other forms of radiation or from damage that can occurbecause of exposure to environments that can damage the components, orbecause of damage that can occur during handling or manipulation of adisplay 60 or that provides protection against mechanical, thermal,chemical or other factors that may damage imaging elements 20 or othercomponents of display 60.

FIG. 7 shows yet another embodiment of an imaging element 20 inaccordance with the present invention. In the embodiment of FIG. 7,imaging element 20 can comprise any of the above-described embodimentsand also incorporates an optional memory 80. Memory 80 is adapted tostore at least one illumination control signal for use in controllingthe light emitted by the illumination circuit 24. This additional storedillumination control signal can be used as a default condition so thatas display 60 is activated, an initial image or default image will bepresented by an array of imaging elements 20 in display 60.Alternatively, memory 80 can have the capability of storing a pluralityof illumination control signals. In such an embodiment, wireless signalscan be provided to select one of the stored illumination control signalsfor presentation using the imaging element 20. Further, wireless controlsignals can be generated that cause wireless communication circuit 22 tostore new illumination control signals in memory 80.

Referring now to FIG. 8, what is shown is an embodiment of imagingelement 20 of FIG. 7 further comprising a radiation sensor 90 and sensordriver 92. Radiation sensor 90 is adapted to sense at least one form ofelectromagnetic radiation by converting such forms of energy into asensed radiation signal. Such forms of radiation can include, but arenot limited to, visible light, x-ray radiation, ultraviolet light, andinfrared light.

Sensor driver 92 is adapted to monitor the sensed radiation signal andto provide a sensed value signal that indicates an amount of radiationincident on radiation sensor 90 during an exposure time. In oneembodiment, the exposure time is a predetermined period of time. Inanother embodiment, the exposure time is determined dynamically withsensor driver 92 establishing an exposure time based upon the amountradiation incident on radiation sensor 90 during a pre-sampling period,or even during an initial portion of the exposure time. In still anotherembodiment, the exposure time can be defined by a device that isexternal to an imaging element 20, with the external device (not shown)transmitting a wireless signal to cause radio frequency receiver circuit30 to transmit a sensor driver control signal. Sensor driver 92 receivesthe sensor driver control signal and can determine the exposure timetherefrom.

In one embodiment of imaging element 20, radiation sensor 90 is adaptedto sense an amount of light radiated by illumination element 38 duringan exposure time and sensor driver 92 is adapted to provide a feedbacksignal that can be used to help guide operation of illumination controlcircuit 36. In this embodiment, illumination control circuit 36 receivesthis feedback signal and compares the amount of light sensed byradiation sensor 90 to an amount of light that illumination controlcircuit 36 should be causing illumination element 38 to radiate inresponse to an illumination control signal in use at the time that thelight is sensed. Illumination controller circuit 36 can use thiscomparison to make automatic adjustments to the amount of energy appliedto illumination element 38 so that illumination element 38 radiates adesired amount of light in response to an illumination value received byillumination control circuit 36.

In other embodiments, sensor driver 92 and radiation sensor 90 can beadapted to sense light emitted by adjacent imaging elements in a displayand/or ambient levels, and an optional adjustment circuit 97 can beprovided that is adapted to adjust the amount of light emitted by animaging element in response to a control signal, with such adjustmentsbeing based upon the sensed amount of light from the adjacent lightlevels and or the ambient light levels.

In another embodiment, sensor driver 92 provides the feedback signal towireless communication circuit 22 which provides a wireless signal to anexternal calibration device (not shown) that is adapted to compare thelight emitted by an imaging element 20 as indicated by the feedbacksignal and an actual amount of light measured by the externalcalibration system so that the external calibration system can transmita correction factor for use by illumination control circuit 36 incontrolling light emitting operations of imaging element 20.

In this way, imaging element 20 can compensate for variations in theefficiency of illumination circuit 24 that arise as a result ofmanufacturing variations and/or variations that can occur inillumination circuit 24 as a result of use or exposure to environmentalirritants over the course of the useful life of imaging element 20.Where advantageous, compensation can also be provided to compensate forvariations in the alignment of imaging elements 20.

Alternatively, imaging element 20 can provide a radiation sensor 90 thatsenses little or no light radiated by illumination element 38. This canbe done by the providing a radiation sensor 90 that is not adapted tosense specific types of light emitted by illumination element 38 or byapplying filter materials within body 40 between illumination element 38and radiation sensor 90 so that light emitted by illumination element 38is absorbed by such filter materials. In another embodiment, radiationsensor 90 can be adapted to sense light that is incident upon imagingelement 20 from a range of areas that are largely unaffected by thelight emitted by illumination element 38. For example, radiation sensor90 can be directed away from illumination element 38 such as by beingpositioned on a side of support 26 that is opposite from a side ofsupport 26 having illumination element 38.

In one embodiment, sensor driver 92 is adapted to generate a data signalthat can be stored in memory 80 that is indicative of an amount ofradiation incident upon radiation sensor 90 during exposure time. Memory80 and sensor driver 92 also can be adapted so that sensor driver 92 canstore multiple sensed radiation data signals in memory 80. In thisembodiment, wireless communication circuit 22 can be adapted to transmita wireless signal providing stored sends radiation signals to a remotedevice so that it is not necessary to immediately upload stored sensedradiation signals. This can be used, for example, to allow a number ofimages to be captured in quick succession and then uploaded at a latertime.

In the embodiment of FIG. 8, wireless communication circuit 22 can havea radio frequency transmitter 94. Radio frequency transmitter 94 can beused to transmit a radio frequency signal having data therein. Examplesof data that can be transmitted by radio frequency transmitter 94include but are not limited to data stored in memory 80, sensedradiation signals from sensor driver 92 and identification code data.

FIG. 9 shows a block diagram schematic of one example of an imagingelement 20 having a radiation sensor 90, sensor driver 92 and radiofrequency transmitter 94 in accordance with the embodiment of FIG. 7. Inthis embodiment, radiation sensor 90 comprises photovoltaic surface forconverting radiation that is incident on the photovoltaic surface intoan electrical output signal. In the configuration of FIG. 9, radiationsensor 90 provides a voltage across a capacitor 96 to an optionalamplifier 98. An optional analog to digital converter 99 accepts theoutput of amplifier 98 as input and provides, as an output, acorresponding digital sensed value signal. In this embodiment, radiofrequency transmitter 94 accepts the digital value from analog todigital converter 99 as input and in combination with antenna 32generates and transmits an encoded electromagnetic signal conditioned bythe sensed value signal.

Referring to FIG. 10, there is shown a block diagram schematic ofimaging element 20 shown in FIG. 8 and adapted for use in sensing x-rayradiation. In this embodiment, X-rays 93 are directly incident on ascintillator element 95 such as a phosphor material that radiatesvisible light when exposed to X-ray radiation. In this embodiment, thescintillator element 95 is within imaging element 20 a coating of aphotosensor or as a deposit of a photosensor in a material forming body40. In response to the level of radiation received, scintillator element95 provides light which is then sensed by a photosensitive radiationsensor 90, buffered by amplifier 98, converted by analog to digitalconverter 99, and encoded, available for transmission by transmitter 94.

Referring now to FIG. 11, still another embodiment of imaging element 20is provided. In the embodiment of FIG. 11, an imaging element 20 isshown having an embodiment of wireless communication circuit 22 that isadapted to receive wireless signals in the form of visible ornon-visible light having an illumination value therein and to generate acontrol signal based thereupon. In the embodiment of FIG. 11, wirelesscommunication circuit comprises radiation sensor 90, and an embodimentof sensor driver 92 that is adapted to sense light signals havingillumination values therein and to provide an illumination controlsignal to operate illumination control circuit 36. Optionally,illumination control circuit 36 can be adapted to modulate light emittedby illumination element 38 to transmit data.

In an alternative embodiment, shown in FIG. 12, wireless communicationcircuit 22 comprises a light sensor 100 such as a photodiode, OLED, PLEDor other sensor of a type that can be used to sense visible light,infrared light, ultraviolet light or other non-visible light and toconvert the sensed light into a sensed light signal and a light receivercircuit 102. Light signal receiver circuit 102 is adapted to receive thesensed light signal and to interpret the sensed light signal. Lightsignal receiver circuit 102 has an identification code that performs thesame function described above with regard to detecting any illuminationvalues stored in the sensed light and to providing an illuminationcontrol signal having a value that is based upon the illumination valuewhen the light signal has the identification code therein. In such anembodiment, light receiver circuit 102 will provide illumination controlsignal to illumination control circuit 36.

In any embodiment of the invention, radiation sensor 90 and radiationcontroller 92 and/or light sensor 100 and light receiver circuit 102 andcan be adapted to extract operational power from sensed radiation.Further, light receiver circuit 102 can also be used to extractoperational power from the sensed radiation. Such extracted power can beapplied for use by any energy consuming circuit or system in such animaging element 20. It will also be appreciated that such a radiationsensor 90 or light sensor 100 can also be capable of extracting powerfrom energy radiated by ambient sources including but not limited tosolar radiation.

In the embodiment shown in FIG. 12, wireless communication circuit 22also comprises a light transmitter circuit 103 that can be used totransmit light signals in the visible or invisible spectrum to a remotereceiver (not shown).

In the embodiment of FIG. 12, a light transmitter circuit 103 drives alight source 104 to generate data modulated light. However, in otherembodiments, light transmitter circuit 103 can provide modulation orother instructional signals to illumination control circuit 36 causingillumination element 38 to be modulated in a manner that conveys data.In certain embodiments, this is done in a manner that is not readilyapparent to an observer, such as by encoding the signal using minorvariations in the power supplied to illumination element 38.

Referring to FIG. 13, there is shown a block diagram view of an imagingsystem 105 comprising a sensing display 106 having a plurality ofimaging elements 20 having a radiation sensor 90 and a sensor driver 92as described above. In this embodiment, a radiation source 107 such asthe sun provides light that strikes an object 108. Light reflected bythe object 108 is sensed by radiation sensors 90 of imaging elements 20.A transceiver 109, controlled by a control logic processor 110, sendsand receives wireless signals to and from imaging elements 20. In thisembodiment, the wireless signals 112 and 114 are radio frequencysignals.

Transceiver 109 is adapted to generate radio frequency signals havinggeneric commands to which all imaging elements 20 in display 106 willrespond. For example, when transceiver 109 is used with an imagingelement 20 having illumination values stored in memory 80, transceiver109 can transmit a “present stored image” signal that causes all of theimaging elements 20 in sensing display 106 to emit an amount of lightdetermined by the stored illumination value. Similarly, transceiver 109can cause an image to be captured by imaging elements 20 of the typehaving radiation sensors 90 by transmitting a generic “capture” signalto each of the imaging elements 20 in sensing display 106 causing thesensor drivers 92 therein to monitor the amount of radiation sensed byradiation sensors 90 for a common exposure period.

Transceiver 109 is also adapted to generate radio frequency signals thatcontain identification codes therein which cause only one of the imagingelements 20 to respond. For example, transceiver 109 a can transmitsignals individually addressed to individual imaging elements 20 causingthe individual imaging elements 20 to emit specific amount of light sothat an image that has not yet been stored in memories 80 of imagingelements 20 can be presented on sensing display 106. Similarly,transceiver 109 can transmit signals individually addressed to imagingelements 20 to individually poll imaging elements 20 so that sensedradiation values can be obtained therefrom in a logical manner. Thesesensed radiation values can be assembled by control logic processor 110to form an electronic image 116 for presentation on a separate displaymonitor 118. Alternatively, transceiver 109 can transmit signals causingimaging elements 20 to radiate light in proportion to an amount of lightsensed during the exposure period. In this way, an image can be capturedand presented using sensing display 106. In one embodiment, sensingdisplay 106 can be used to cause illumination elements 38 of imagingelements 20 to act as radiation sources 107 to emit light that isreflected, for example, by object 108 and sensed by radiation sensors90.

Among the useful applications for a sensing display 106 of imagingelements 20 is the capture of images of non visible light. Specifically,as shown above, it is possible to use imaging elements 20 that are of atype that is specially adapted for the purpose of sensing x-ray light.However, as shown in FIG. 14, imaging elements 20 that are adapted forcapturing visible light can be used for such a purpose when ascintillator plate 120 is positioned proximate to be imaging elements20. Scintillator plate 120, can be for example as a fluorescent screenthat emits a pattern of visible light 121 when exposed to a pattern ofx-ray light 122. As shown in FIG. 14, sensing display 106 is positionedproximate to scintillator plate 120 in an arrangement suitable forobtaining a high-resolution image. An image sensing operation is thenperformed as described above.

Communications Schemes

It can readily be appreciated that the use of miniaturized imagingelements 20, while eliminating the need to form a complex backplane,imposes a requirement for a significant amount of wireless communicationin order to read or write data to each of the imaging elements 20 usefulin a sensing display 106. Even with a sensing display 106 having a 200dpi resolution, display 106 of the present invention would have200×200=40,000 RF devices, that is, 40,000 imaging elements 20, persquare inch. To make communication more efficient, various types ofpolling and grouping schemes may be employed.

Referring again to FIG. 14, there is shown an arrangement of groupingtransceivers 124 on a sensing display 106 for communicating with imagingelements 20. Each grouping transceiver 124 communicates with a set ofimaging elements 20. Such a set can comprise for example between 2 and2000 imaging elements. This arrangement reduces the number of RFtransactions that must then be executed between transceiver 109 andcomponents within sensing display 106.

Referring to FIG. 15, there is shown another arrangement that extendsthe use of grouping transceivers 124 on an embodiment of sensing display106 further having one or more sets of intermediate groupingtransceivers 126. These intermediate transceivers 126 are deployed forfurther relaying of the image-bearing RF signals on sensing display 106.By cascading grouping transceivers 124 in this fashion, the transfer ofa complete image between a transceiver 109 and imaging elements 20 ofsensing display 106 can be performed in a fraction of the time thatwould be required for individual polling of imaging elements 20. It willalso be appreciated that grouping transceivers 124 and intermediategrouping transceivers 126 can be used with a display 60.

Fabrication Using Fluidic Self Assembly

Referring to FIG. 16, there is shown, in a partial side viewrepresentation, a placement arrangement for imaging elements 20 onsensing display 106 using Fluidic Self-Assembly (FSA) as described inU.S. Pat. No. 5,545,291 entitled “Method for fabricating self-assemblingmicrostructures” and filed by Smith et al. on Dec. 17, 1993. Inconventional FSA techniques, a substrate such as substrate 128 isprovided having a plurality of cavities 130 on a surface 132 such asfirst layer 62. A liquid 134 is combined with items such as imagingelements 20 to form a slurry 136. Slurry 136 is applied to surface 132and the suspended items flow into the cavities and assemble thereto.Liquid 134 is then evaporated or may be retained, such as sealed withinsensing display 106, for example. At the end of the assembly process,each cavity 130 in a surface 132 has at least one imaging elementdeposited therein.

FSA techniques allow a fairly accurate placement of individual imagingelements 20 into individual cavities 130, however, it is possible that asmall percentage of cavities 130 are empty. In a preferred embodiment,cavity 130 is dimensioned to allow, at most, a single imaging element20; however, there may be applications for which larger cavities 130 maybe more desirable, even at the risk of multiple imaging elements 20 in asingle cavity 130. In such a case, duplicate imaging elements 20 couldbe detected and disabled.

Where imaging elements 20 have a preferred orientation it will benecessary to provide systems that are compatible with FSA techniques toensure that imaging elements 20 are fixed in such an orientation. FSAtechniques may provide the preferred orientation, such as by shapingwalls 138 of each cavity 130 to have a shape that corresponds to a shapeof an engagement surface 83 on body 40 of each imaging element 20 sothat each imaging element 20 can engage cavity 130 in only oneorientation.

As noted above, in an alternative embodiment, imaging elements 20 can beadapted to positionally react when exposed to an electromagnetic fieldsuch as by magnetically polarizing the imaging elements 20 in slurry,and then applying a magnetic field orient imaging elements 20. Referringto FIG. 17, one example of this is shown. In the example of FIG. 17, amagnet 140 that is passed along surface 136 of substrate 128 in order tocorrectly orient imaging elements 20. Magnet 140 could be any of anumber of types of magnets, such as permanent or electromagnetic types,for example.

In an alternate embodiment, body 40 of imaging element 20 is adapted todiffuse, reflect, or otherwise modify received and/or transmittedradiation and/or light so that orientation is not critical. For example,body 40 can be defined to have an arrangement of walls 146 that are atleast partially reflective, in a pattern that allows any light incidenton any portion of body 40 to be distributed for sensing by radiationsensor 90 without regard to the orientation of radiation sensor.Similarly body 40 can have an arrangement of outer surface 42 that isdefined to have a pattern that causes light emitted by illuminationelement 38 to be distributed so that the light is evenly distributed toprovide generally uniform illumination despite the orientation ofdisplay element 30.

Imaging Elements Applied in a Coating

An alternate embodiment for manufacturing a display 60 or sensingdisplay 106 uses a coating process to apply imaging elements 20.Miniaturization of imaging element 20 components allows these componentsto be suspended within a liquid coating medium 142 for application to asurface 144 such as first layer 62 or some other substrate 146 in one ormore coats without necessarily creating cavities 130 in first layer 62.

FIG. 18 shows an embodiment in which a display 60 or a sensing display106 is fabricated using coating methods to deposit imaging elements 20onto substrate 128. Coating methods can be similar to applying a paintor other finish, with the additional requirement for having imagingelements 20 suspended within the coating medium 142. Conventional bindertypes can be used in coating medium 142 for suspending imaging elements20 during coating and for securing imaging elements 20 into place onsubstrate 128. Typical binder types include conventional polymericbinders used for paint and finish coatings. Any of a variety of bindertypes including acrylic, alkyds, epoxies, polyester urethane, or vinylresins could be used, for example. As is shown in FIG. 18, someirregularity in the distribution of imaging elements 20 can beanticipated. Following the coating process, a number of imaging elements20 may be oriented at a variety of angles with respect to surface 132 ofsubstrate 126. There may be other irregularities in distribution, suchas gaps and overlaps, as is shown in the plane view of FIG. 19, and thesectional view of FIG. 20.

In order to provide a suitable image and represent the image in an arrayof unevenly spaced pixels, using conventional imaging methods, varioustypes of imaging algorithms can be employed. Imaging algorithms, forexample, would apply interpolation to determine the value of a pixelbased upon nearby values. Where imaging elements 20 overlap, it may evenbe necessary to apply an averaging algorithm or to disable the unneededimaging element 20, depending on the requirements of the imagingapplication. Thus, while it would be optimal to provide a uniformdensity coverage for imaging elements 20 over a unit area of substrate128, there are various methods available for effectively smoothing outdistribution irregularities of imaging elements 20.

Coating medium 142 may itself provide a protective layer over imagingelements 20 once they are applied to substrate 146. Optionally, as isshown in FIG. 20, a separate display overcoat 148 could be applied atopimaging elements 20 and/or coating medium 142. Display overcoat 148could be any number of materials. In one embodiment, display overcoat148 is a transparent polyurethane; however, display overcoat 148 couldhave various properties for handling light, including diffusive orfiltering properties. Display overcoat 148 could act as a type of colorfilter, for example, blocking light of certain wavelengths, so that onlylight of a selected wavelength is sensed by imaging elements 20. Displayovercoat 148 could also be a phosphorescent material for absorbing andradiating light energy at certain useful wavelengths, for example. Useof a diffusive phosphorescent material could be advantageous, forexample, where imaging elements 20 are skewed at angles rather thanparallel to the surface of substrate 126 as was shown in FIGS. 18 and19.

Multiple coating layers could be applied to obtain improved uniformityor to apply different types of components with each coating operationproviding layer and components as described generally above with respectto FIG. 5. For example, a first coating could be applied for positioninggrouping transceivers 124 on one layer. A second coating could beapplied atop this first layer to position imaging elements 20 on sensingdisplay 106.

Double-Sided Embodiments for Sensing Display

Referring to FIG. 21, there is shown an embodiment in which a display 60or sensing display 106 is double-sided, having imaging elements 20disposed on first side 150 and second side 152 of substrate 128. Thisarrangement allows a number of options for use of display 60 or sensingdisplay 106. Optionally, where substrate 146 is transparent, imagingelements 20 on both sides of sensing display 106 could be used tocapture an image of the same scene at higher resolution.

As shown in FIG. 21, imaging elements 20, first conductors 64 and secondconductors 66 and second layer 68 can be provided on one side ofsubstrate 128 with first conductors 155 and second conductors 157 and aninsulator layer 153 having imaging elements 20 therein can be formed onanother side of substrate 128. Additional layers, such as second layer68 and additional second layer 159, can also be applied as needed. Inanother optional embodiment, both first side 150 and second side 152 ofsensing display 106 could be provided with a phosphor coating forabsorbing radiation energy for subsequent scanning and sensing usingimaging elements 20.

Calibration of Displays

Whether or not imaging elements 20 are arranged in an orderly matrixarrangement, using cavities 130 as was described with reference to FIGS.16 and 17 or randomly distributed using the coating method describedwith reference to FIGS. 18 and 19, each display 60 or sensing display106 should have some mechanism for determining location information thatassociates each imaging element 20 with the location of each imagingelement 20 on display 60 and sensing display 106. This can be done, forexample by assigning Cartesian (x,y), polar coordinates or other logicaltwo-dimensional or even three dimensional location information for eachimaging element 20.

FIG. 22 illustrates another embodiment of a method for determininglocation information for associating each imaging element 20 with alocation on a sensing display 106. This embodiment, an externalcalibration system applies a radiation pattern 162 to known locations onsensing display 106. The radiation pattern 162 can be a single point 164as shown, or it can comprise multiple points. The imaging elements 20 onsensing display 106 are polled during exposure. Each imaging element 20that is exposed to the radiation can respond to the polling with signalsindicative of such exposure and address information. Where groupingtransceivers 124 and/or intermediate grouping transceivers 126 are usedfor example in a sensing display 06 having imaging elements 20, aresponsive signal can be received therefrom that provides addressinformation or other information that identifies the groupingtransceiver and the intermediate grouping transceiver.

Because the location on the sensing display 106 that is exposedradiation is known, it can be determined that the imaging element 20 orimaging elements 20 that respond with signals indicative of each suchexposure are located at the position of exposure. Location informationthat links each such location with responsive imaging elements isstored. The pattern of radiation 162 is swept across sensing display 106following a sweep path 166, one example of which is shown in FIG. 23,until imaging elements 20 are identified for each location in a displayarea of sensing display 106. Conversely, a similar approach can be usedin which signals are sent causing individual ones of the imaging element20 to radiate light, and by determining the location of the lightradiating imaging element 20.

The method outlined above also allows a type of calibration for eachimaging element 20. The radiation pattern 162 provides a signal of knownstrength to known areas of display 106. However, in other embodiments,radiation source 152 can comprise other light sources such as linearrays. The response signal may indicate, for example, the angularposition of imaging element 20, which may not be at the angle of surface132 as was described with reference to FIG. 18. Alternatively, theresponse can be a function of the efficiency of illumination elements 38of imaging elements 20. This information can be used to providecalibration information for each imaging element 20. In embodimentswherein imaging element 20 has a radiation sensor 90 that is adapted tosense radiation emitted by illumination element 38, radiation sensor 90and sensor driver 92 can provide such a signal for communication to anexternal device which can use this signal to determine calibrationinformation based upon this signal.

In another embodiment, a different method for determining locationinformation associating a position of any individual imaging element 20on the surface of a sensing display 106 is to use triangulation. Withthis method, each point is located based on its relative distance fromand direction from a set of three reference points. Referring to FIG.21, there is shown sensing display 106 having a randomized array ofimaging elements 20. Imaging elements 20 a, 20 b, and 20 c serve asreference points for the triangularization process. Based on thecoordinates of reference points 20 a, 20 b, and 20 c, any fourth pointcan be located, as is represented by point 20 d, for example. Thetriangularization process can be carried out iteratively for all imagingelements 20 on the surface of sensing display 106, using the samereference points of imaging elements 20 a, 20 b, and 20 c. Optionally,different sets of reference points can be used for obtaining relativecoordinates for other imaging elements 20 on the surface of sensingdisplay 106. Triangularization logic can use methods to determinerelative distance based on comparative signal strength or may usemethods for determining the angular direction of a signal source.

There are a variety of forms in which the grain location information canbe stored. The stored imaging element 20 location information couldcomprise, in one specific embodiment, a data Look-Up Table (LUT)correlating a imaging element 20 identifier to a coordinate position(x,y) could be maintained. Using this method, imaging element 20 doesnot need to store its coordinate position data in an internal memory.For example, each imaging element 20 can be preprogrammed with a uniqueaddress that is provided each time that the imaging element 20 respondsto the polling signal. In this embodiment, the imaging element locationdata comprises a look-up table that associates each address of a imagingelement 20 with the location on display 106 that energy was applied toadd a point when the respective imaging element 20 provided a signalindicative of exposure to the energy.

In another embodiment, each imaging element 20 is adapted to receive andstore location information indicating the location on sensing display106 at which energy was applied at a time when the respective imagingelement 20 provided a signal indicative of exposure to such energy. Inthis embodiment, therefore, each time, after calibration, that theimaging elements 20 of sensing display 106 are polled, such digitalimaging elements 20 will respond with a signal indicating the intensityof the exposure and the location of the grain reporting the intensitysignal. This allows for rapid reconstruction of a digital image usingthe information provided in response to the polling signal.

It will be appreciated that while these methods have been described withreference to a sensing display 106, they are equally applicable todetermining the location of imaging elements 20 that are not adapted tosense radiation.

In still another embodiment, imaging element location information can,at least in part, the stored in memories in a grouping transceiver 124and/or intermediate grouping transceiver 126.

Sensing/Display Element Embodiment

In certain of the above described embodiments, imaging elements 20 havebeen described that incorporate illumination element 38 and a radiationsensor 90 that are provided in the form of separate components. However,in the embodiment shown in FIG. 24, an imaging element 20 is providedthat is adapted to use a single material for both light emission andradiation sensing. In the embodiment shown in FIG. 24 an imaging elementis provided having a anode layer 170, a diode layer 172 and asubstantially transparent conductive layer 174 assembled about asubstrate 26 having a communication circuit 22, an illumination controlcircuit 24 and a sensor driver 92. In this embodiment, both ofillumination control circuit 24 and sensor driver 92 are adapted withelectrical connections to a combined illumination element 38 andradiation sensor 90 having the anode layer 170, diode layer 172 and/orconductive layer 174 so that electrical signals can be provided to orreceived from the anode layer 170, diode layer 172 and/or conductivelayer 174. In this embodiment, the material for the diode layercomprises an organic or inorganic diode material that is capable ofemitting light when driven in a first manner by illumination controlcircuit 24 and capable of sensing light when driven by or otherwiseinteracting with sensor driver 92. Examples of material that can be usedin this fashion include OLED and PLED materials. When a potentialdifference is applied across a cathode and anode disposed about a supplyof such material, electrons from the electron injecting layer and holesfrom the hole injecting layer are injected into the light emittinglayer, they recombine, emitting light. This process can be reversed sothat exposure of such materials to light causes such materials togenerate a difference in potential across the cathode and anode whenexposed to light. Examples of such OLEDs and PLEDs are described in thefollowing United States patents, all of which are incorporated herein bythis reference: U.S. Pat. No. 5,707,745 to Forrest et al., U.S. Pat. No.5,721,160 to Forrest et al., U.S. Pat. No. 5,757,026 to Forrest et al.,U.S. Pat. No. 5,834,893 to Bulovic et al., U.S. Pat. No. 5,861,219 toThompson et al., U.S. Pat. No. 5,904,916 to Tang et al., U.S. Pat. No.5,986,401 to Thompson et al., U.S. Pat. No. 5,998,803 to Forrest et al.,U.S. Pat. No. 6,013,538 to Burrows et al., U.S. Pat. No. 6,046,543 toBulovic et al., U.S. Pat. No. 6,048,573 to Tang et al., U.S. Pat. No.6,048,630 to Burrows et al., U.S. Pat. No. 6,066,357 to Tang et al.,U.S. Pat. No. 6,125,226 to Forrest et al., U.S. Pat. No. 6,137,223 toHung et al., U.S. Pat. No. 6,242,115 to Thompson et al., and U.S. Pat.No. 6,274,980 to Burrows et al.

Another example of a material that can be used in this fashion is aninorganic LED material such as a material fabricated from III-V compoundsemi-conductors and a material II-VI semi-conductors. When a forwarddifference of potential is applied across junctions formed in thesedevices electron in holes injected into the device recombine, emittinglight. This process can be reversed so that the exposure of suchmaterials to light causes generation of electron hole pairs; theseelectron hole pairs, known in the art as carriers can be sensed eitheras a current or as change in potential.

Those of skill in the art will recognize that a variety of other typesof materials and devices are known that have the capability to both emitand sense light and can be used in like fashion.

It will be appreciated that this embodiment, the size of a sensing andlight emitting imaging element 20 can be reduced as compared to the sizeof a sensing and light emitting imaging element that requires a separateillumination element 38 and radiation sensor 90. It will also beappreciated that embodiments such as the embodiments of FIGS. 1B and 1Ccan be adapted with such a light emitting and sensing material and aradiation sensor 92 for use in a sensing and emitting embodiment ofimaging element 20.

In this or other embodiments, an imaging element 20 having a radiationsensor 90, communication circuit 22 can be adapted to receiveillumination values or to transmit a signal based on sensed radiationusing digital or analog wireless communication schemes. In an analogexample, communication circuit 22 can have a voltage controlledoscillator and a mixer that adjust the frequency of radio frequencysignals to provide a sensed voltage level signal that can be detected,for example by a grouping transceiver 124 which then converts thissignal into a digital signal for transmission to a transceiver asgenerally described above.

Multiple Part Illumination Element

As is shown in FIG. 25, in certain applications, it can be useful toprovide an illumination element 38 that is capable of emitting more thanone separately controllable type of light. For example, it can be usefulto provide an imaging element 20 that is capable of generating multiplecolors of light, or of generating light that is both in the visible andnon-visible bands. In the example shown in FIG. 25, imaging element 20has three parts, a red part 38 a that emits red light, a blue part 38 bthat emits blue light, and a green part 38 c that emits green light. Bycontrolling the amount of light emitted by each of parts 38 a, 38 b and38 c, a wide range of colors can be emitted.

The invention has been described with reference to a preferredembodiment. However, it will be appreciated that variations andmodifications can be effected by a person of ordinary skill in the artwithout departing from the scope of the invention.

PARTS LIST

-   20 imaging element-   22 wireless communication circuit.-   24 light source-   26 support-   30 radio frequency receiver circuit-   32 antenna-   35 electrodes-   36 illumination control circuit-   37 deposit of light emitting material-   38 illumination element-   38 a-38 c illumination element parts body-   42 outer surface of body-   44 first electrically conductive portion-   46 second electrically conductive portion-   48 electrical insulator-   52 electrical conductor-   54 electrical conductor-   60 display-   62 first layer-   64 first conductive layer-   66 second conductive layer-   68 second layer-   69 top surface-   70 overcoat layer-   71 array-   72 insulative layer-   74 power supply-   76 battery layer-   78 interlayer power connector-   80 memory-   90 radiation sensor-   92 sensor driver-   93 X-rays-   94 radio frequency transmitter-   95 scintillator element-   96 capacitor-   97 adjustment circuit-   98 amplifier-   99 analog to digital converter-   100 light sensor-   102 light receiver circuit-   103 light transmitter circuit-   104 light source-   105 imaging system-   106 sensing display device-   107 radiation source-   108 object-   109 transceiver-   110 control logic processor-   112 wireless signal-   114 wireless signal-   116 display monitor-   118 electronic image-   120 scintillator plate-   121 visible light-   122 X-ray light-   124 grouping transceiver-   126 intermediate grouping transceiver-   128 substrate-   130 cavity-   132 surface-   134 liquid-   138 wall-   140 magnet-   142 coating medium-   144 surface-   146 walls-   148 overcoat-   150 first side-   152 second side-   153 insulator layer-   155 first conductor-   157 second conductor-   159 additional second layer-   162 radiation pattern-   164 sweep path-   166 sweep path-   170 anode layer-   172 diode layer-   174 transport conductive layer-   M Microlens

1-14. (canceled)
 15. An imaging element comprising: a wirelesscommunication circuit adapted to detect a wireless communication signaland to generate a control signal; an illumination circuit having anillumination element, said illumination circuit being adapted so thatthe illumination element generates light at an intensity that is basedupon the control signal; and a body containing the wirelesscommunication circuit and the light source; wherein said body occupies aspace that is less than about five cubic millimeters, wherein saidimaging element is polarized for orientation when exposed to anelectro-magnetic field. 16-17. (canceled)
 18. An imaging elementcomprising: a radiation sensor adapted to sense radiation that isincident on the radiation sensor during an exposure period; a sensordriver adapted to determine an amount of radiation incident on theradiation sensor during the exposure period; an illumination circuithaving an illumination element, the illumination circuit being adaptedso that the illumination element generates light at an intensity that isbased upon a control signal; a wireless communication circuit adapted todetect a wireless communication signal and to generate a control signalbased upon the wireless communication signal and further adapted togenerate a wireless communication signal indicative of the amount ofsensed radiation during an exposure period; and a body containing thewireless communication circuit and the light source; wherein said bodyoccupies a space that is less than about five cubic millimeters.
 19. Theimaging element of claim 18, wherein said wireless communication circuitis further adapted to detect a wireless communication circuit having anaddress for the imaging element therein and to generate a control signalin response thereto and further adapted to generate a wirelesscommunication signal having the address for the imaging element andindicative of the amount of sensed radiation.
 20. The imaging element ofclaim 18, wherein said wireless communication circuit is adapted toextract power from a wireless signal for use in light sensing, lightgeneration or wireless communication.
 21. The imaging element of claim18, further comprising conductive portions adapted to engage a powersource that is external to the body so that power from the externalpower source is available for use by the illumination circuit, theradiation sensor, the sensor driver, or the wireless communicationcircuit.
 22. The imaging element of claim 21, wherein said conductiveportions are adapted to engage power source to obtain power foroperation therefrom.
 23. The imaging element of claim 18, furthercomprising a memory adapted to store at least one sensed light signalbased upon the amount of light sensed by the light sensor during anexposure period.
 24. The imaging element of claim 18, further comprisinga memory adapted to store more than one sensed value signal based uponan amount of light sensed by the light sensor during a set of more thanone exposure periods and wherein said wireless communication circuit isadapted to provide a wireless communication signal that contains one ormore stored sensed value signals.
 25. The imaging element of claim 18,wherein said imaging element is formed on a support with the radiationsensor and illumination element oriented in a common direction withrespect to the support.
 26. The imaging element of claim 18, whereinsaid imaging element comprises a base with the radiation sensor andlight emitter oriented differently on the base.
 27. The imaging elementof claim 18, wherein said radiation sensor is operable to sense anamount of light emitted by the illumination element further comprising acalibration circuit adapted to adjust the amount of light emitted by thelight source to correspond to an amount of light that is to be generatedby the light source in response to the control signal.
 28. The imagingelement of claim 18, wherein said radiation sensor is adapted to senseat least eon of an amount of light emitted by other proximate imagingelements or an ambient amount of light and further comprises acompensation circuit adapted to adjust the amount of light radiated bythe illumination element in response to a received illumination valuebased upon the sensed amount of light.
 29. The imaging element of claim18, wherein location information associating a location on the displaywith imaging elements is stored in a memory of the imaging elements. 30.The imaging element of claim 18, wherein location informationassociating a location on the display with imaging elements is stored ina memory on the display.
 31. The imaging element of claim 18, whereinlocation information associating a location on the display with imagingelements is stored in a memory that is remote from the display.
 32. Animaging element comprising: a radiation sensor adapted to senseradiation that is incident on the radiation sensor including the amountof light emitted by the illumination element; a sensor driver adapted todetermine an amount of radiation radiated by the illumination elementbased upon the sensed radiation during an exposure period; anillumination circuit having an illumination element, the illuminationcircuit being adapted so that the illumination element generates lightat an intensity that is based upon a control signal; a calibrationcircuit adapted to monitor the amount of light sensed by the radiationsensor and to adjust the amount of light emitted by the illuminationelement in response to control signals so that the amount of lightcorresponds to an amount of light that is to be generated by theillumination circuit in response to the control signal; and a bodycontaining the wireless communication circuit and the light source. 33.The imaging element of claim 29, further comprising wirelesscommunication circuit adapted to detect a wireless communication signaland to generate a control signal based upon an illumination value in thewireless communication signal, to generate a wireless communicationsignal indicative of the amount of sensed radiation during an exposureperiod and to receive a signal from an external device indicating acorrection factor to be used in adjusting the amount of light emitted bythe illumination element in response to the control signal.
 34. Theimaging element of claim 29, further comprising a sensor driver andradiation sensor that is adapted to sense light emitted by one ofadjacent imaging elements in a display and ambient light levels, and anadjustment circuit that is adapted to adjust the amount of light emittedby an imaging element in response to a control signal, with suchadjustments being based upon the sensed amount of light from theadjacent light levels and or the ambient light levels.
 35. An imagingelement comprising: a radiation sensing and emitting material operableto provide a signal indicative of radiation that is incident on theradiation sensor and to generate radiation when energy is introducedinto the radiation sensing and emitting material; a sensor driveradapted to determine an amount of radiation sensed by the radiationsensing and emitting material; an illumination circuit, the illuminationcircuit being adapted to controllably introduce energy into theradiation sensing and emitting material so that the radiation sensingmaterial generates emits radiation at an intensity that is based upon acontrol signal; a wireless communication circuit adapted to detect awireless communication signal and to generate a control signal basedupon the wireless communication signal and further adapted to generate awireless communication signal indicative of the amount of sensedradiation during an exposure period; and a body containing the wirelesscommunication circuit and the light source; wherein said body occupies aspace that is less than about five cubic millimeters.
 36. The imagingelement of claim 34, wherein the radiation sensing and emitting materialis disposed between a pair of conductors at least one of which issubstantially transparent.